Users report that they are unable to connect to a server. An administrator confirms that it is unreachable across the network. Other administrators have been working in the server room throughout the

Verifying the switch port configuration is a valid troubleshooting step but should occur after confirming that the physical cable connection is secure, as a disconnected cable would make port configuration irrelevant.

Rebooting the server should be considered after checking physical connections and other basic diagnostics, as it causes service disruption and will not resolve a disconnected cable.

Installing a new NIC is a drastic measure for troubleshooting and implies a hardware failure, which should only be considered after ruling out simpler and more common issues like cabling or configuration problems.

Given that other administrators were working in the server room, a common and easily remedied cause for a server being unreachable is a disconnected or loose network cable. Verifying physical connections is the most fundamental and quickest initial step in network troubleshooting, as it addresses issues at the physical layer (Layer 1).